Surgical stapling device with flexible shaft

ABSTRACT

A surgical stapling device includes a housing assembly that is coupled to a tool assembly by a flexible elongate body that having an outer tube, a middle tube, and an inner cable. Each of the outer tube and the inner cable has a proximal end portion fixedly connected to the housing assembly and a distal end portion that is fixedly connected to the tool assembly. The middle tube is positioned within the outer tube about the inner cable and is movable from a retracted position to an advanced position to operate the tool assembly.

FIELD

The technology is generally related to surgical stapling devices and, more particularly, to endoscopic surgical stapling devices with flexible shafts.

BACKGROUND

Surgical stapling devices for performing surgical procedures endoscopically are known and are commonly used in a variety of surgical procedures to minimize patient trauma and reduce patient recovery time. These devices include tool assembly having an anvil assembly, a cartridge assembly, and a drive assembly for ejecting staples from the cartridge assembly into the anvil. The tool assembly may have a variety of configurations including linear, circular, and curved.

In linear endoscopic stapling devices, the drive assembly often includes a flexible beam that is advanced through the tool assembly to eject staples from the cartridge assembly and to cut tissue clamped between the anvil and cartridge assemblies. Typically, the flexible beam can only bend in a single plane.

During many endoscopic surgical procedures, it is necessary to access surgical sites that are confined. In such procedures maneuverability of the tool assembly at the surgical site to gain access to tissue is critical. A continuing need exists in the art for an endoscopic stapling device having improved maneuverability to better access tissue at the surgical site.

SUMMARY

The disclosure is directed to a surgical stapling device including a housing assembly that is coupled to a tool assembly by a flexible elongate body that having an outer tube, a middle tube, and an inner cable. Each of the outer tube and the inner cable has a proximal end portion that is fixedly connected to the housing assembly and a distal end portion that is fixedly connected to the tool assembly. The middle tube is movable within the outer tube about the inner cable from a retracted position to an advanced position to operate the tool assembly. Each of the outer and middle tubes and the inner cable are formed from a flexible material. The inner cable and the outer tube stabilize and prevent buckling of the middle tube during actuation of the stapling device.

Aspects of the disclosure are directed to a surgical stapling device including a housing assembly, an elongate body, and a tool assembly. The housing assembly includes a body defining a cavity and a drive mechanism positioned within the cavity. The elongate body includes an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube. The outer tube, middle tube, and inner cable are formed of flexible materials. The tool assembly includes an anvil assembly, a cartridge assembly, and a clamp member. The cartridge assembly is movable in relation to the anvil assembly between open and clamped positions and includes a cartridge body and a plurality of staples. The cartridge body defines a plurality of staple receiving slots. Each of the staple receiving slots receives one of the plurality of staples. The clamp member is movable within the tool assembly from a retracted position to an advanced position to eject the plurality of staples from the cartridge body. The inner cable includes a proximal end portion fixedly coupled to the body of the housing assembly and a distal end portion fixedly coupled to the tool assembly. The middle tube includes a proximal end portion coupled to the drive mechanism and a distal end portion coupled to the clamp member. The outer tube has a proximal end portion coupled to the body of the housing assembly and a distal end portion coupled to the tool assembly. The drive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the clamp member between its retracted and advanced positions.

Other aspects of the disclosure are directed to a surgical device including a housing assembly, an elongate body, a tool assembly, and an inner cable tensioning mechanism. The housing assembly includes a body defining a cavity and a drive mechanism positioned within the cavity. The elongate body includes an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube. The tool assembly is supported on the elongate body and includes an operating member. The inner cable includes a proximal end portion fixedly coupled to the body of the housing assembly and a distal end portion fixedly coupled to the tool assembly. The middle tube includes a proximal end portion coupled to the drive mechanism and a distal end portion coupled to the operating member. The outer tube includes a proximal end portion coupled to the body of the housing assembly and a distal end portion coupled to the tool assembly. The inner cable tensioning mechanism includes a shaft and a turnabout supported on the shaft within the cavity of the body of the housing assembly. The inner cable is wrapped about the turnabout. The drive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the operating member between its retracted and advanced positions.

Other aspects of the disclosure are directed to a surgical stapling device including a housing, an elongate body, and a tool assembly. The housing supports a drive mechanism. The elongate body includes an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube. The outer tube, middle tube, and inner cable are formed of flexible materials. The tool assembly includes an anvil assembly, a cartridge assembly, and a clamp member. The cartridge assembly is movable in relation to the anvil assembly between open and clamped positions and includes a cartridge body and a plurality of staples. The cartridge body defines a plurality of staple receiving slots. Each of the staple receiving slots receives one of the plurality of staples. The clamp member is movable within the tool assembly from a retracted position to an advanced position to eject the plurality of staples from the cartridge body. The inner cable includes a proximal end portion that is fixedly coupled to the body of the housing assembly and a distal end portion that is fixedly coupled to the tool assembly. The middle tube includes a proximal end portion that is coupled to the drive mechanism and a distal end portion that is coupled to the clamp member. The outer tube has a proximal end portion that is coupled to the body of the housing assembly and a distal end portion that is coupled to the tool assembly. The drive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the clamp member between its retracted and advanced positions.

In aspects of the disclosure, the drive mechanism includes a drive nut that is movable within the cavity of the body of the housing assembly between retracted and advanced positions and the proximal end portion of the middle tube is coupled to the drive nut.

In some aspects of the disclosure, the drive mechanism includes a lead screw that is rotatably supported within the cavity and is operably engaged with the drive nut.

In certain aspects of the disclosure, the drive nut defines a threaded bore and the lead screw extends through the threaded bore and is rotatable to move the drive nut between its retracted and advanced positions.

In aspects of the disclosure, the surgical stapling device includes an inner cable tensioning mechanism having a shaft and a turnabout supported on the shaft within the cavity of the body of the housing assembly, and the inner cable is wrapped about the turnabout.

In some aspects of the disclosure, the shaft includes a threaded screw and the body of the housing assembly defines a threaded bore, wherein the threaded screw is received within the threaded bore of the body of the housing assembly and is rotatable to adjust the position of the turnabout within the housing assembly to adjust tension of the inner cable.

In certain aspects of the disclosure, the turnabout includes a distal end portion defining a curved surface and the inner cable extends along the curved surface of the turnabout.

In aspects of the disclosure, the middle tube defines a longitudinal slot positioned within the cavity of the body of the housing assembly and the inner cable extends through the longitudinal slot about the turnabout.

In some aspects of the disclosure, the cartridge assembly includes an actuation sled that is movable within the cartridge body from a retracted position to an advanced position in response to movement of the clamp member from its retracted position to its advanced position to eject the plurality of staples from the cartridge body.

In certain aspects of the disclosure, the cartridge assembly includes a knife that is movable from a retracted position to an advanced position in response to movement of the clamp member from its retracted position to its advanced position to cut tissue clamped between the anvil and cartridge assemblies.

Other features of the disclosure will be appreciated from the following description.

BRIEF DESCRIPTION OF DRAWINGS

Various aspects of the disclosure are described herein below with reference to the drawings, wherein:

FIG. 1 is a perspective view of exemplary aspects of the disclosed surgical stapling device including a tool assembly in an open, non-articulated position;

FIG. 2 is a perspective view of the surgical stapling device shown in FIG. 1 with the tool assembly in a clamped, articulated position;

FIG. 3 is a side perspective, exploded view of the housing assembly of the stapling device shown in FIG. 2;

FIG. 4 is a cross-sectional view of the stapling device shown in FIG. 1;

FIG. 5 is an enlarged view of the indicated area of detail shown in FIG. 4 with the stapling device in the open position;

FIG. 6 is a side perspective, exploded view of the tool assembly of the stapling device shown in FIG. 2;

FIG. 7 is an enlarged view of the indicated area of detail shown in FIG. 5 with the stapling device in the open position;

FIG. 8 is a cross-sectional view of the housing assembly shown in FIG. 6 with the stapling device in the pre-fired clamped position;

FIG. 9 is a cross-sectional view of the tool assembly shown in FIG. 7 with the stapling device in the pre-fired clamped position;

FIG. 10 is a cross-sectional view of the housing assembly shown in FIG. 8 with the stapling device in the clamped and fired position;

FIG. 11 is a cross-sectional view of the tool assembly shown in FIG. 9 with the stapling device in the fired and clamped position;

FIG. 12 is a cross-sectional view of the housing assembly shown in FIG. 10 with the stapling device in the clamped and fired position as a drive assembly is retracted from the fired position; and

FIG. 13 is a cross-sectional view of the tool assembly shown in FIG. 11 with the stapling device in the fired and clamped position as the drive assembly is retracted from the fired position.

DETAILED DESCRIPTION

Exemplary aspects of the disclosed surgical stapling device will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the aspects of the disclosure are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure. Directional terms such as front, rear, upper, lower, top, bottom, distal, proximal, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, the term “endoscopic” is used generally used to refer to endoscopic, laparoscopic, arthroscopic, and/or any other procedure conducted through a small diameter incision or cannula. Further, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel.

FIGS. 1 and 2 illustrate exemplary aspects of the disclosed surgical stapling device shown generally as stapling device 10. The stapling device 10 includes a housing assembly 12, an elongate body 14, and a tool assembly 16. The housing assembly 12 has a body 18 that defines a cavity 18 a (FIG. 5) that receives other components of the housing assembly 12 as described below. The elongate body 14 is flexible and includes an outer tube 22, a middle tube 24, and an inner cable 26. The outer tube 22 of the elongate body 14 has a proximal end portion 28 and a distal end portion 30. The proximal end portion 28 of the outer tube 22 is fixedly secured to the body 18 of the housing assembly 12 and the distal end portion 30 of the outer tube 22 is fixedly coupled to the tool assembly 16 to control spacing between the housing assembly 12 and the tool assembly 16.

The middle tube 24 extends through the outer tube 22 and includes a proximal end portion 34 (FIG. 4) and a distal end portion 36. The proximal end portion 36 of the middle tube 24 is coupled to a drive mechanism 40 located within the body 18 of the housing assembly 12 and the distal end portion 36 of the middle tube 24 is coupled to a clamp member 42 of the tool assembly 16. An upper surface of the middle tube 24 defines an elongate longitudinal slot 38. The drive mechanism 40 can be actuated as described in further detail below to advance the middle tube 24 within the outer tube 22 to advance the clamp member 42 within the tool assembly 16.

The inner cable 26 extends through the middle tube 24 and includes a proximal end portion 46 (FIG. 3) and a distal end portion 48. The proximal end portion 46 of the inner cable 26 extends through the slot 38 in the middle tube 24 within the cavity 18 a and is coupled to the body 18 of the housing assembly 12. The distal end of the inner cable 26 is fixedly coupled to the tool assembly 16. The middle tube 24 is movable about and along the inner cable 26 within the outer tube 22 as described in further detail below.

In aspects of the disclosure, each of the outer and middle tubes 22, 24, respectively, and the inner cable 26 is formed of a flexible material. In some aspects of the disclosure, one or all of the outer and middle tubes 22, 24 and the inner cable 26 are formed of stranded wire cables formed from, e.g., stainless steel. It is also envisioned that one or all of the outer and middle tubes 22, 24 and the inner cable 26 could be formed from other materials including synthetic polymers, nylon, tungsten etc. In some aspects of the disclosure, the inner cable 26 is formed from tungsten for added strength.

FIGS. 3-5 illustrate the housing assembly 12 which includes the body 18, the drive mechanism 40, and an inner cable tensioning mechanism 50. The body 18 includes a main body portion 52 and a proximal cover 54. The main body portion 52 defines the cavity 18 a (FIG. 5) and includes a distal wall 56, an upper wall 58, side walls 60, and a bottom wall 62. The distal wall 56 defines a first bore 64, a second bore 66, and a third bore 68. In certain aspects of the disclosure, the first bore 64 is stepped and receives the proximal end portion 28 of the outer tube 22. It is envisioned that the outer tube 22 can be secured within the first bore 64 of the distal wall 56 of the body 18 using any of a variety of securement techniques including welding, adhesion, or the like. The second bore 66 is threaded and receives the tensioning mechanism 50 as described in detail below.

The proximal cover 54 is secured to a proximal portion of the body 18 and includes a first bore 70 and a second bore 72. The first bore 70 of the proximal cover 54 receives a lead screw 76 of the drive mechanism 40 of the stapling device 10 and the second bore 72 of the proximal cover 54 receives a bolt 78. The bolt 78 extends through the second bore 72 and is threaded into a threaded bore 80 (FIG. 5) formed in the proximal portion of the body 18 of the housing assembly 12 to secure the proximal cover 54 to the main body portion 52 of the body 18 of the housing assembly 12.

The drive mechanism 40 includes the lead screw 76, a drive nut 84, and a driver insert 86. The drive nut 84 defines a threaded bore 88 and a through bore 90. The threaded bore 90 receives the lead screw 76 such that rotation of the lead screw 76 causes longitudinal movement of the drive nut 84 within the cavity 18 a of the body 18 of the housing assembly 12 between retracted and advanced positions. The proximal end of the lead screw 76 includes an annular flange 92 and is supported within the main body portion 52 of the housing assembly 12 on spaced bearings 94. One of the spaced bearings 94 is positioned on each side of the annular flange 92 to support the lead screw 76 for rotation within the cavity 18 a of the body 18 of the housing assembly 12.

The proximal end portion 34 of the middle tube 24 defines a blind bore 96 (FIG. 5) that is threaded. The drive nut 84 is coupled to the proximal end portion 34 of the middle tube 24 by a threaded bolt 98 that extends through the bore 90 of the drive nut 84 and into the threaded bore 96 of the middle tube 24. The driver insert 86 is tubular and is received about the proximal end portion 34 of the middle tube 24 within the bore 90 of the drive nut 84. The driver insert 86 provides rigidity and support for the proximal end portion 34 of the middle tube 24 in the area of the threaded connection between the middle tube 24 and the threaded bolt 98. By coupling the proximal end portion 34 of the middle tube 24 to the drive nut 84, longitudinal movement of the drive nut 84 within the cavity 18 a of the body 18 of the housing assembly 12 causes corresponding longitudinal movement of the middle tube 24 within the cavity 18 a to move the middle tube 24 within the outer tube 22 along the inner cable 26.

The inner cable tensioning mechanism 50 includes and a shaft 100 and a turnabout 102 that is supported on the shaft 100 for longitudinal movement. In aspects of the disclosure, the shaft 100 includes a threaded screw 100 and the turnabout 102 includes a body 104 having a proximal end portion defining a threaded bore 106 and a distal end portion defining a curved surface 108. In certain aspects of the disclosure, the curved surface 108 extends over an arc of about 180 degrees although other degrees of curvature are envisioned. The threaded screw 100 includes a proximal portion that is received within the second bore 66 of the body 18 of the housing assembly 12 and a distal portion that supports the turnabout 102. The threaded screw 100 is rotatable within the second bore 66 of the body 18 of the housing assembly 12 to adjust the longitudinal position of the turnabout 102 within the cavity 18 a of the body 18 of the housing assembly 12.

As described above, the inner cable 26 includes a proximal end portion 46 that is fixedly secured to the body 18 of the housing assembly 12. In certain aspects of the disclosure, the proximal end portion 46 of the inner cable 26 extends from the tool assembly 16 proximally through the outer and middle tubes 22, 24, respectively, and through the first bore 64 in the distal wall 56 of the body 18 of the housing assembly 12 and into the cavity 18 a. Within the cavity 18 a of the body 18 of the housing assembly 12, the inner cable 26 extends proximally and exits the middle tube 24 through the longitudinal slot 38 defined in the middle tube 24. After the inner cable 26 exits the slot 38, the inner cable 26 is wrapped around the turnabout 102 such that the proximal end portion 46 of the inner cable 26 is redirected distally and is coupled to the distal wall 56 of the body 18. In aspects of the disclosure, the proximal end portion 46 of the inner cable 26 extends through the bore 68 in the distal wall 56 of the body 18 to secure the inner cable 26 to the body 18. The body 18 can include an elongated slot, e.g., slot 103 to accommodate the redirection of the inner cable 26. It is envisioned that the inner cable 26 could be secured to the body 18 of the housing assembly 12 at a variety of different locations using a variety of securement techniques.

The inner cable tensioning mechanism 50 functions to set the desired tension in the inner cable 26 during the manufacturing process. In that respect, a distal end of the screw 100 can be adapted to receive a tool, e.g., a screw driver, Allen wrench, or the like, to adjust the position of the screw 100 and turnabout 102 within the cavity 18 a of the body 18 of the housing assembly 12. Since the proximal and distal end portions 46, 48, respectively, are fixedly secured to the housing assembly 12 and the tool assembly 16, respectively, adjusting the position of the turnabout 102 within the cavity 18 a increases or decreases the tension in the inner cable 26.

FIGS. 6 and 7 illustrate the tool assembly 16 which includes an anvil assembly 110, a cartridge assembly 112, and a pivot housing 114. Briefly, the anvil assembly 110 includes an anvil body 116 and an anvil plate 118 that are secured together to define a channel 120 within the anvil assembly 110. The anvil plate 118 defines a central knife slot 122 that extends through a tissue clamping surface 124 (FIG. 7) of the anvil plate 118 and communicates with the channel 120.

The cartridge assembly 112 includes a channel 124 and a staple cartridge 126 that is received within the channel 124. The staple cartridge assembly 126 includes a cartridge body 128, staples 130, pushers 132, an actuation sled and knife assembly 134, and a lower cover 136. The cartridge body 136 defines rows of staple receiving pockets 140 (FIG. 6) and a central knife slot 142 (FIG. 6) that is aligned with the knife slot 122 formed in the anvil plate 118. The staples 130 and the pushers 132 are supported within the staple receiving pockets 140 of the cartridge body 128 on a respective one of the pushers 132. The actuation sled and knife assembly 134 includes an actuation sled 134 a and a pivotable knife 134 b. The actuation sled 134 a includes camming surfaces that engage the pushers 132 when the actuation sled 134 a is driven through the cartridge body 128 to drive the staples 130 from the cartridge body 136. The knife 134 b is supported on the actuation sled 134 a and translates through the knife slots 122, 142 in the cartridge body 128 and the channel 124, respectively, as the actuation sled 134 a is driven through the cartridge body 136 to cut tissue clamped between the anvil and cartridge assemblies 110, 112. It is envisioned that the knife 134 b could be stationary and supported on the clamp member 42. For a more detailed description of the operation of the actuation sled and knife assembly 134, see, e.g., U.S. Pat. No. 8,973,805 (“the '805 patent”).

The anvil assembly 110 and the cartridge assembly 112 are coupled to the pivot housing 114 by pivot members 150 (FIG. 6). The pivot members 150 allow the cartridge assembly 112 to pivot in relation to the anvil assembly 110 between an open position (FIG. 7) and a clamped position (FIG. 9). In aspects of the disclosure, biasing members 154 (FIG. 6) urge the tool assembly 16 towards the open position. It is envisioned that tool assembly 16 can also include an anvil assembly 110 that pivots towards a stationary cartridge assembly 112 or anvil and cartridge assemblies that pivot towards each other.

The clamp member 42 is supported on the tool assembly 16 and is aligned with the actuation sled 134 a. The clamp member 42 includes an upper beam 42 a that positioned to engage the anvil assembly 110 and a lower beam 42 b that is positioned to engage the channel 124 of the cartridge assembly 112. The clamp member 42 is movable within the tool assembly 16 from a retracted position to an advanced position in response to advancement of the middle tube 24 as described in further detail below. As the clamp member 42 is moved through the tool assembly 16, the tool assembly 16 moves from the open position to the clamped position and, subsequently engages and advances the actuation sled 134 a through the cartridge body 128 to eject the staples 130 from the staple cartridge body 128. For a more detailed description of the operation of the clamp member 42, see the '805 patent.

The channel 124 of the cartridge assembly 112 includes a distal upturned flange 160 (FIG. 6) that defines an opening 162. The distal end portion 48 of the inner cable 26 extends through the staple cartridge body 128 along the channel 124 and is fixedly received within the opening 162 to secure the inner cable 26 to the channel 124. Alternately, it is envisioned that the distal portion of the inner cable 26 could be secured to the channel 124 at a variety of different locations using a variety of different securement techniques.

The distal end portion 30 of the outer tube 22 is fixedly secured to a proximal face 168 of the pivot housing 114, e.g., welding or the like. The middle tube 24 extends through the outer tube 22 and is secured to a proximal surface 170 of the clamp member 42, e.g., by welding or the like. In some aspects of the disclosure, the proximal face 170 of the clamp member 42 defines a circular recess 172 that receives the distal end portion 36 of the middle tube 24 to more securely fasten the middle tube 26 to the clamp member 42.

Although not described herein, a proximal end of the housing assembly 12 is adapted and configured to engage an actuator (not shown) that is capable of selectively rotating the lead screw 76 of the housing assembly 12. The actuator (not shown) can be in the form of a hand held powered hand piece or in the form of a robotic device.

FIGS. 8 and 9 illustrate the stapling device 10 as the stapling device 10 is moved from the open position to the clamped position. When the stapling device 10 is actuated by rotating the lead screw 76 in the direction indicated by arrow “A” in FIG. 8, engagement between threads on the lead screw 76 and threads within the threaded bore 88 of the drive nut 84 cause the drive nut 84 to move longitudinally in the direction of arrow “B within the cavity 18 a of the body 18 of the housing assembly 12. It is noted that the drive nut 84 is prevented from rotating within the cavity 18 a of the body 18 of the housing assembly 12 by walls of the body 18. As the drive nut 84 moved within the body 18 of the housing assembly 12, the middle tube 24 which is fixedly coupled to the drive nut 84 is advanced within the outer tube 22 about the inner tube 26. Movement of the middle tube distally about the inner cable 22 applies a force on the tool assembly 16 in the distal direction which places the inner cable 26 in tension. As noted above, the inner cable 26 is fixedly coupled to both the housing assembly 12 and to the tool assembly 16 to prevent distal movement of the tool assembly 16 in relation to the housing assembly 12. As the middle tube 24 moves distally within the outer tube 22, the clamp member 42, which is fixedly coupled to the distal end portion 36 of the middle tube 24, moves distally within the tool assembly 16 in the direction indicated by arrow “D” in FIG. 9. The positioning of the middle tube 24 about the inner cable 26 and within the outer tube 22 provides stability to the middle tube 24 to prevent buckling of the middle tube 24.

When the clamp member 42 moves from its retracted position within the tool assembly 16 towards its advanced position, the upper and lower beams 42 a, 42 b, respectively, of the clamp member 42 engage the anvil assembly 110 and the cartridge assembly 112, respectively, to pivot the cartridge assembly 112 in relation to the anvil assembly 110 in the direction of arrow “D” in FIG. 9 to move the tool assembly 16 from the open position to the clamped position.

FIGS. 10 and 11 illustrate the stapling device 10 as the stapling device 10 is fired. In order to fire the stapling device 10, the lead screw 76 is rotated again in the direction of arrow “A” in FIG. 10 to advance the drive nut 84 further distally within the body 18 of the housing assembly 12 in the direction of arrows “C” in FIG. 10. As the drive nut 84 continues to advance within the body 18 of the housing assembly 12, the middle tube 24 continues to advance within the outer tube 22 along the inner cable 26 in the direction of arrows “D” in FIGS. 10 and 11. As the middle tube 24 advances through the tool assembly 16, the clamp member 42 moves through the tool assembly 16 into engagement with the actuation sled 134 a to advance the actuation sled 134 a through the tool assembly 16. As the actuation sled 134 a moves through the tool assembly 16, the actuation sled 134 engages the pushers 132 (FIG. 6) to drive the staples 130 from the cartridge body 128 of the cartridge assembly 112 into the anvil assembly 110. As noted above, the pivotable knife 134 b is coupled to the actuation sled 134 a. As such, the pivotable knife 134 b is moved distally through the tool assembly 16 with the actuation sled 134 a. As known in the art, the knife 134 b moves through the knife slots 122, 142 in the anvil plate 118 and the cartridge body 128, respectively, to cut tissue clamped between the anvil assembly 110 and the cartridge assembly 112.

FIGS. 12 and 13 illustrate the stapling device 10 after the tool assembly 16 has been fired as the clamp member 42 is moved from its advanced position back towards its retracted position. In order to retract the clamp member 42, the lead screw 76 is rotated in in a direction opposite to that shown by arrow “A” in FIG. 10, i.e., in the direction indicated by arrow “E” in FIG. 12. As the lead screw 76 rotates in the direction indicated by arrow “E”, the drive nut 84 moves proximally within the housing assembly 12 in the direction indicated by arrow “F” in FIGS. 12 and 13. As the drive nut 84 moves proximally within the housing assembly 12, the middle tube 24 is pulled proximally about the inner cable 26 within the outer tube 22 to pull the clamp member 42 proximally within the tool assembly 16 in the direction indicated by arrows “G” in FIG. 13. As the middle tube 24 moves proximally within the outer tube 22 and pulls the clamp member 42 proximally within the tool assembly 16, a proximally directed force is applied to the tool assembly 16 which places the outer tube 22 in compression.

Persons skilled in the art will understand that the stapling devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with certain aspects of the disclosure may be combined with the elements and features of other aspects of the disclosure without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects of the disclosure. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A surgical stapling device comprising: a housing assembly including a body defining a cavity, and a drive mechanism positioned within the cavity; an elongate body including an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube, the outer tube, middle tube, and inner cable being formed of flexible materials; and a tool assembly including an anvil assembly, a cartridge assembly, and a clamp member, the cartridge assembly movable in relation to the anvil assembly between open and clamped positions and including a cartridge body and a plurality of staples, the cartridge body defining a plurality of staple receiving slots, each of the staple receiving slots receiving one of the plurality of staples, the clamp member movable within the tool assembly from a retracted position to an advanced position to eject the plurality of staples from the cartridge body; the inner cable including a proximal end portion fixedly coupled to the body of the housing assembly and a distal end portion fixedly coupled to the tool assembly, the middle tube including a proximal end portion coupled to the drive mechanism and a distal end portion coupled to the clamp member, and the outer tube having a proximal end portion coupled to the body of the housing assembly and a distal end portion coupled to the tool assembly; wherein the dive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the clamp member between its retracted and advanced positions.
 2. The surgical stapling device of claim 1, wherein the drive mechanism includes a drive nut that is movable within the cavity of the body of the housing assembly between retracted and advanced positions, the proximal end portion of the middle tube coupled to the drive nut.
 3. The surgical stapling device of claim 2, wherein the drive mechanism includes a lead screw rotatably supported within the cavity, the lead screw operably engaged with the drive nut.
 4. The surgical stapling device of claim 3, wherein the drive nut defines a threaded bore, the lead screw extending through the threaded bore and being rotatable to move the drive nut between its retracted and advanced positions.
 5. The surgical stapling device of claim 1, further including an inner cable tensioning mechanism including a shaft and a turnabout supported on the shaft within the cavity of the body of the housing assembly, the inner cable wrapped about the turnabout.
 6. The surgical stapling device of claim 5, wherein the shaft includes a threaded screw and the body of the housing assembly defines a threaded bore, the threaded screw received within the threaded bore of the body of the housing assembly and being rotatable to adjust the position of the turnabout within the housing to adjust tension of the inner cable.
 7. The surgical stapling device of claim 6, wherein the turnabout includes a distal end portion defining a curved surface, the inner cable extending along the curved surface of the turnabout.
 8. The surgical stapling device of claim 7, wherein the middle tube defines a longitudinal slot positioned within the cavity of the body of the housing assembly, the inner cable extending through the longitudinal slot of the middle tube and about the turnabout.
 9. The surgical stapling device of claim 1, wherein the cartridge assembly includes an actuation sled, the actuation sled movable within the cartridge body from a retracted position to an advanced position in response to movement of the clamp member from its retracted position to its advanced position to eject the plurality of staples from the cartridge body.
 10. The surgical stapling device of claim 9, wherein the cartridge assembly includes a knife, the knife movable from a retracted position to an advanced position in response to movement of the clamp member from its retracted position to its advanced position to cut tissue clamped between the anvil and cartridge assemblies.
 11. A surgical stapling device comprising: a housing assembly including a body defining a cavity, and a drive mechanism positioned within the cavity; an elongate body including an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube, the outer tube, middle tube, and inner cable formed from flexible materials; and a tool assembly supported on the elongate body including an operating member; the inner cable including a proximal end portion fixedly coupled to the body of the housing assembly and a distal end portion fixedly coupled to the tool assembly, the middle tube including a proximal end portion coupled to the drive mechanism and a distal end portion coupled to the operating member, and the outer tube having a proximal end portion coupled to the body of the housing assembly and a distal end portion coupled to the tool assembly; and an inner cable tensioning mechanism including a shaft and a turnabout supported on the shaft within the cavity of the body of the housing assembly, the inner cable wrapped about the turnabout; wherein the drive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the operating member between its retracted and advanced positions.
 12. The surgical stapling device of claim 11, wherein the tool assembly further includes an anvil assembly and a cartridge assembly, and the operating member includes a clamp member, the cartridge assembly movable in relation to the anvil assembly between open and clamped positions and including a cartridge body and a plurality of staples, the cartridge body defining a plurality of staple receiving slots, each of the staple receiving slots receiving one of the plurality of staples, the clamp member movable within the tool assembly from a retracted position to an advanced position to eject the plurality of staples from the cartridge body.
 13. The surgical stapling device of claim 11, wherein the drive mechanism includes a drive nut that is movable within the cavity of the body of the housing assembly between retracted and advanced positions, the proximal end portion of the middle tube coupled to the drive nut.
 14. The surgical stapling device of claim 13, wherein the drive nut defines a threaded bore, the lead screw extending through the threaded bore and being rotatable to move the drive nut between its retracted and advanced positions.
 15. The surgical stapling device of claim 14, wherein the shaft includes a threaded screw and the body of the housing assembly defines a threaded bore, the threaded screw received within the threaded bore of the body of the housing assembly and being rotatable to adjust the position of the turnabout within the housing to adjust tension of the inner cable.
 16. The surgical stapling device of claim 15, wherein the turnabout includes a distal end portion defining a curved surface, the inner cable extending along the curved surface of the turnabout.
 17. The surgical stapling device of claim 16, wherein the middle tube defines a longitudinal slot positioned within the cavity of the body of the housing assembly, the inner cable extending through the longitudinal slot of the middle tube and about the turnabout.
 18. A surgical stapling device comprising: a housing supporting a drive mechanism; an elongate body including an outer tube, a middle tube extending through the outer tube, and an inner cable extending through the middle tube, the outer tube, middle tube, and inner cable being formed of a flexible materials; and a tool assembly including an anvil assembly, a cartridge assembly, and a clamp member, the cartridge assembly movable in relation to the anvil assembly between open and clamped positions and including a cartridge body and a plurality of staples, the cartridge body defining a plurality of staple receiving slots, each of the staple receiving slots receiving one of the plurality of staples, the clamp member movable within the tool assembly from a retracted position to an advanced position to eject the plurality of staples from the cartridge body; the inner cable including a proximal end portion fixedly coupled to the body of the housing assembly and a distal end portion fixedly coupled to the tool assembly, the middle tube including a proximal end portion coupled to the drive mechanism and a distal end portion coupled to the clamp member, and the outer tube having a proximal end portion coupled to the body of the housing assembly and a distal end portion coupled to the tool assembly; wherein the dive mechanism is actuable to advance the middle tube within the outer tube along the inner cable to advance the clamp member between its retracted and advanced positions.
 19. The surgical stapling device of claim 18, further including an inner cable tensioning mechanism supported on the housing, the inner cable tensioning mechanism including a threaded screw and a turnabout supported on the threaded screw, the inner cable wrapped about the turnabout, the housing defining a threaded bore, the threaded screw received within the threaded bore of the body of the housing assembly and being rotatable to adjust the position of the turnabout within the housing to adjust tension of the inner cable.
 20. The surgical stapling device of claim 19, wherein the drive mechanism includes a drive nut that is movable along the housing assembly between retracted and advanced positions, the proximal end portion of the middle tube coupled to the drive nut. 